Creping of paper in the longitudinal direction



CREPING OF PAPER IN THE LONGITUDINAL DIRECTION Filed Dec. 16, 1932UNITED STATES PATENT. OFFICE 1,986,070 canrmo or PAPER- m rnr.Lomn'ummr.

nmacrron HermannRoaenfelQGer-mauy Application Deoember 1c, 1932-, SerialNo. 647,688 In Germany December 21, 1931 6 Claims. (01. 154-33) Myinvention relates to the creping of paper in the longitudinal direction.

It is an object of my invention to provide a method for creping longwebs, such as. the webs 5 delivered from paper-making machines.

To this end, I perform the longitudinal creping of the websprogressively, for instance stepwise.

It has already been attempted to crepe paper in itslongitudinaldirection only, or to crepe it in several directions but the methodswhich have been proposed for this purpose,'were not suitable for crepinglongitudinally long and continuous webs such as are delivered bypaper-making machines, but at the most permit the creping of shortstrips or paper and not creping on a quantity-production basis. I

- It has also been attempted to crepe longitudinally continuous webs ofpaper by subjecting moist paper to an upsetting action for aconsiderable length. In this manner, suitable lonfeature of my method isthat the creping or' creasing pressure is exerted only on acomparatively small portion of the paper at a time so that the width'ofthe paper is reduced stepwise. Preferably, the paper, although it maybe creped longitudinally only, is creped transversely as well by one ofthe usual methods, so that the product as finished has longitudinal aswell as transverse creping and, as compared with paper creped in onedirection only, is very resilient in all directions and suitable forpurposes for which 40 paper with creping in one direction only could notbe used on account of its insuflicient stretch.

In performing my method, I may proceed stepwise so as to form creaseafter crease until the web has been creased or creped'longitudinally allover its width. The creping may be performed by starting from one of theedges of the web and progressing toward the interior, or by startingfrom both edges, or by starting from the interior and progressing towardone, or both edges.

As mentioned, the gradual character oi! my method is important. Forinstance, consider a web which is 100 centimetres (about one yard) widein its initial condition. During the first creping or creasing stage,the paper reduced for about in., i. e. to a width of 99 centimetres, inthesecond stage to 98 centimetres, and so on, stepwise, until the finalwidth has been attained.

In the accompanying drawing, a machine for performing my methodstepwise, and various 5 ways of operating the machine, are illustrateddiagrammatically by way of example.

In the drawing:

Fig. 1 is a diagram of the machine,

Fig. 2 is a diagram of the operation illustrated for the machine in Fig.1,

5 Fig. 3 is a diagram showinghow the operation is started from theinterior of the web, and progresses toward both edges, 7

Fig. 4 shows the formation of several crease at a time,

Fig. 5 shows a web having longitudinal creases only,'and

Fig. 6 shows a web having longitudinal and transverse creases.

' Referring now to the drawing, and first to Figs. 1 and 2, P is a webof paper, and I, II n are the stages of creping. 1 is a creasing tool,and 2 is an abutting member. In the first stage I, the tool 1 and themember 2 form a crease 1' which extends in the longitudinal direction ofthe web, by moving them at right angles to the direction in which theweb is fed.- The means for operating the tool 1 and the member 2 havenotbeen shown and may be of any suitable type. The first creasing operationreduces the width of the web for the amount. d. In the second stage II,the operation is repeated by forming a second crease 1 reducing 35 thewidth of the web again for the amount d, so that the total reduction isnow 2d. The first crease 1 has moved inwardly for the amount d. In thethird and fourth stages, III and IV, creases 1 and 1 are formed in thesame manner and at the same pitch d, until finally in the stage n thecrease 1 is formed at the distance mi from the edge of the web in itsinitial position. The web has now been creased for the desired width.

It will be understood that in the example-described the longitudinalcreping of the web is efiected stepwise and by upsetting, but I am notlimited to this particular type of progressive creping, nor am I limitedto the use of upsetting tools as shown, but may use stamping, drawing,or any other type of mechanical, or even pneumatic tools. Thesevariations have not been shown but will bereadily understood by anyexpert.

other.

Fig. 2 shows the progressive formation of the creases 1' etc. and itshows how the creping progresses gradually and step by step from theedge at the left over the width of the web. The straight lines at 1'etc. show the points of attack of the tools 1 and the members 2. Thelines together make up a broken line extending longitudinally from oneend of the web to the Instead of beginning with the creping operation atone edge, I may begin with both edges and gradually progress toward theinterior of the web.

Another possibility is starting at the centre 01' the web as shown inFig. 3, by forming a pair of creases 1 there, andprogressing toward bothedges from the starting pair of creases.

Still another possibility is the formation of several creases per stage,as shown in Fig. 4 where three creases per stage are formed at L, L,etc. This reduces the time for creping a web of a given width.

There'should not be too many points of attack for the tools and members1 and 2, nor should the points he pitched too closely as this leads toan undesirable excessive distortion of the paper.

The web may be creped while moving and whilestationary/ For instance, itis possible to perform the creping operation in cooperation with theformation of the web on a papermaking machine, and onthe still moistweb. Moistening the web may also be desirable in the creping of a webwhich does not come directly from the paper-making machine.

I may also produce a pattern on the web by arranging the creping creasesl'etc. at various points of the web on a given system. Or the creasesmay be omitted at certain points to obtain the pattern.

My invention further relates to the paper obtained by my method which,as shown in Fig. 5, may be creased longitudinally only, as at 1, orlongitudinally and transversely, as shown at 1 and q in Fig. 6.

It is obvious that the comparatively short webs shown are illustratedmerely by way of example and that in fact my method is applied to. longwebs, its particular object being the treatment of long webs such as aredelivered by paper-making machines, and the webs, as mentudinallycomprising creasing said web across its edges and parallel to the planeof the paper web along a portion of its width only while continuouslymoving said web in a lengthwise direction and gradually extending thecreasing across the width of the web until the paper is provided withcreases throughout its width.

3. The method of creping paper webs longitudinally comprising creasingthe web during its feed over a small distance transversely to its edgesand parallel to the plane of the paper web while holding the remainingpart of the web fast against transverse movement so that the web islongitudinally creped within said distance, and extending the creasingprogressively to adjacent parts across the web.

4. The method of forming longitudinally creped paper webs by creasingthe web in a stepwise manner in a plane parallel to the paper web acrossits width over a limited distance in each step and during the feed ofthe web in a lengthwise direction, said stepwise creasing beginning atthe edges of the web and progressing inwardly.

5. The method of forming longitudinally creped paper webs by creasingthe web in a stepwise manner in a plane parallel to the paper web acrossits width over a limited distance in each step and during the feed ofthe web in a lengthwise direction, said stepwise creasing beginning inthe interior of the webs and progressing outwardly.

6. The method of creping paper webs as defined in claim 1, characterizedby the fact that the creasing is started simultaneously at severaldifferent parts of the paper web.

HERMANN ROSEN'FELD.

